Bomb dropping device



July 30, 1940. R. L. BELL 4 2,209,380

BOMB DROPPING nEvIcE Filed sept. 19, 193e "7 sheets-sheet 1 c p INCREAS Lem' F on DIS'IAl'K July so, 1946. R. L. BELL l 2,269,380

BOMB DROPPING DEVICE Filed Sept. 19. 1938 7 Sheets-Sheet 2 july 30,. 1940- R. L. BELL 2,209,380

` BOMB DROPPING DEVICE Filed Sept. 19, 1958 7 Sheets-Shea?.` 5

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l ff 3o 4@ s4? '2S v .j o f2@ las July 3o, 1940. R, L, BELL 2,209,380

BOMB DROPPING DEVICE Filed sept. 19, 19:58 7 sheets-sheet 4 R. I.. SEEE 2,209,380

BOMB DROPPING DEVICE Filed Sept. 19, 1938 '7 Sheets-Sheet 5 il gl@ CD P-BoII/IB PEESELECTR O I PusI-I IENQB. ROTA-IE EITHER DIRECTION..A 1- INDICATOR-@omas REMAINING IN RACES. M

ADJUST ON GROUND WITH WRENCH. G ROTATE .COUNTER-CLOCKWISE.

rI/uIz/Yvbofa- RALPH L. BELL.

uy 3G, 1940.

R. 1.. BELL. 2,209,380

BOMB DROPPING DEVICE Filed Sept. 19, 1938 7 Sheets-Sheet 6 l Q l5.

l RALPH L, BELL Ro 9a Juny so, 1940. R, L, BE| L 22m-3@ BOMB DROPPING DEVI CE Filed Sept. 19, 1938 7 Sheets-Sheet 7 Ime/whom RALPH L. BELL accesso no nnorrma nevica Ralph L. Bell Application September 19, 1938, Serial No. 239,732

21 cia..

determined number of equally spaced impulses, Fis

with means for varying the space therebetween. It is particularly-applicable to the transmission of electrical impulses.

One of the objects of the present invention is to provide a switch of this type which is of simple structure and yet operates with certainty and accuracy, and is useful for many purposes.

Another object is to provide an arrangement of l5, this type with means to control the dropping of a series of bombs, and to -indcate visually the number o bombs remaining' in the series for whichthe device has been set which have not yet been dropped. In a modied form, means are also provided to show at any time the number of bombs remaining in the bomb rack. v Another object of the invention is to provide a mechanism which makes it possible to vary and to control automaticallythe space between the points at which successive bombs strike the earth when dropped by the device while indicating the spacing visually. Particularly, it is an object to provide such an arrangement in which the ground speed of the aircraft is taken into account.

Further objects of the invention will appear more fully from the following description, particularly when taken in commotion with the accompanying drawings, which form 'a part thereof.

In the dra:

Fig. 1 is a front view oi' a release switch made according to the invention;

Fig.'2 is a top plan view of the same;

Fig. 3 is a cross section on the line 3-3 of Fig. 4;

Fig. 4 is a cross section on the line @-4 of Fis. 2;

5 Fis. 4;

' Fig. 6 is a cross section substantially on the line 6-5 of Fig. 2;

Fig. .'lzis'a ragmental cross section on the line of Fis. 3; Fig. 8 is a cross section on the line 8-8 of 7; F18. 9 is mech 1| ,l ra

Fig. 10 is a wiring diagram of the device;

Fig. 5 is a cross section on the line 5-5 of a detail elevationy of the step by step (Si. 8e-l.5)

Fig. 11 is a detail cross section on the line li-il of Fig. 3; c

Fig. 12 is a cross section on the line-i2-i2 of Fig. 2;

Fig. 13 is a cross section on the line itl-i3 of 5 9; y Fig. 14 shows in iront view a ed form of mechanism for controlling and indicating the Y number of bombs dropped in a series;

Fig. 15 is a cross section principally on the m line iS-ii of Fig. 14; Fig. 16 is a cross section substantially on the line I-IG of Fig. 15.

The object of the invention is to impart a series of electrical impulses to any well known type of bomb dropping mechanism which drops one bomb each time an electrical impulse is supplied thereto. In the past it been known to supply such impulses either from a manually controlled switch or from a bomb sight in which an electrical impulse is emitted when the bomb t is properly aligned with the wget. The structure of the present device makes it possible upon the sta of anelectrical impulse either from the bomb sight or manually to drop a series of bombs, of any desired numbe at points equally spaced along the ground. The invention also makes it --\::ble to vary both the number of bombs and the space between the points at which the bombs at will, the signed to take into account the groun the aircrait in spacing the im to the bomb Referring now to 10, there is ahown'a source of current 2 connected through a master switch c to a firing or control key e and thence through a selector switch c to a lead i@ running to the bomb dropping 1. .f Obviously when the master switch e is and the selector switch 8 is in its lett-hand tion `the closing of the key 6 will an impulse directly to the bomb dropping v.v :L `u... of line ill and the device then 'operates purely ually.

0n the other hand, when the switch 8 isin its right-hand position current ilows'into the controlling device generally indicated at i2 which forms the subject matter of this invention and operates the same, as will be described hereinafter.

In order to utilize the device while tting its vremoval from the aircraft when it is not needed, it is arranged so that it can be plugged in by plugs le, i6 and .le connected respectively to wires 2S, 22, and 2c, wire 29 being connected to wire i0, wire 22 to. t-hand contact o! 65 switch 8 and wire 24 to the terminal oi master switch 4.

'I'he device comprises a shunt wound electric motor 26 which is operated by current from plug I6 through a wire 28, and main switch 30. This current is supplied to the motor amature 32 through a rheostat 34 and to the motor field 36 through a eld rheostat 38. Oi course the other terminals of the armature and eld windings are grounded.

In order to vary the speed of the motor 26, I provide means for selectively controlling the re. sistance of the armature and iield rheostats 34 and 38. The movable contact members 40 and 42 respectively of these two rheostats are connected with sprocket wheels 44 and 46 bothof which are engaged by a single chain 48. Chain 48 passes around a sprocket 50 on the end of a shaft 52 which is adapted to be manipulated by a handle or knob 64 on the front wall 66 of the device.

The main motor shaft 58 has mounted thereon a disc 60 provided (see Fig. 11) with a peripheral strip 62 of conductive material, this strip not extending completely around the wheel 68 and leaving a gap as at 64. Against the periphery of the disc are engaged spring contacts 66 and 88 connected respectively through line 10 to plug I6 andl through line 412 to the mechanism to be described below. y

It will be evident that as the motor turns the circuit from wire 10 to wire 12 will be interrupted once at each revolution, since space 64 is widerv than the space between contacts 66 and 88. Furthermore, by varying the speed of the motor, which can be accomplished by turning knob 64, it will'be possible to vary the time between electrical impulses vsent into the line 12.

In order to determine the eiect on the spacing of the bombs of this variation in the speed of the motor, I provide a tachometer 14 which is driven through an auxiliary motor shaft 16. bevelled gears 18 and an interrupted shaft 80 the parts of which are connected by a coil spring 82 (Figs. '1 and 8). The tachometer is provided with a dial 84 (Fig. 1) on which are a series of circles 83 marked `to indicate ditl'erent ground speeds, as, for instance, in miles per hour, and a series ofV curves 85 intersecting these circles and marked to indicate the spaces between bombs. If now the knob 54 is adjusted to vary the-speed of the motor until the pointer 86 of the tachometer intersects that one of the circles which represents the ground speed of the aircraft, say the 200 miles per hour circle, at the point where such circle is cut by the curve |50, this will Indicate that the speed of the motoris such that its electrical im-` pulses occur at periods of time during which the plane is traversing 150 ft. with respect to the 1 provide a shaft as ground, or, in other words, that if a bomb is dropped at each impulse these bombs will strike the ground at distances of 150 It. apart. The operator is thus able, knowing the speed of the aircraft, to set the speed of the motor such that the bombs will drop with the desired spacing.

The second part of the mechanism now' to be described relates to the dropping of a number of bombs in succession, such number having been predetermined by the operator, and the spacing therebetween being determined by the arrangement previously described.

In the left-hand portion of the device (Fig. 1) adapted to be turned by a knob carrying a dial 82, this dial being graduated from 0 to 9 or to any suitable number.

Mounted on the shaft 88 are two discs 84 and 86 generally similar to'the disc 60 vof Fig. 11 (see Fig. 12). The nonconducting spaces on discs 84 and 86 are aligned onshat 88. Cooperating with these discs are contacts 88, |00 and |02, |04 respectively. Contacts 88 and |02 are connected to line 12. Contact |00 is connected through line |06, plug I4 and line 20 to line I0 leading to the bomb dropping mechanism.

Contact |04 is connected to the stepby1step mechanism shown in Fig. 9. This mechanism comprises a solenoid |08 connected to contact |04 and tothe ground. The solenoid acts on a rod I|0 carrying a pin II2 engaged in a slot ||4 in lever ||6 which is mounted to turn on shaft 88. Lever ||6 extends through a slot ||1 in rod |I0 (Figs. 9 and 13). Frictionally mounted on shaft 88 is a ratchet gear II8. A pawl |20 pivot 'i on lever I8 engages the teeth of ratchet gear I :d A secon'd pawl |22 mounted on a lpivot |24 also cngages ratchet ||8. Suitable means are provided for holding these pawls inengagement with the ratchet. A coil spring |26 connected at one end to a xed portion |28 and at its other to the rod I I0 constantly urges the lever I I6 towards the left in Fig. 9. A stop |30 limits the movement of the lever under the action of the spring |26.

supposing now that it is desired to drop six bombs in succession. Knob 80 will be turned until the indication 6 on dial 92 comes opposite the ends |32 of. the front Wall 56. Assuming that the switch 30 is closed, as by handle |34, current will flow through the motor and cause the motor to run, and at the same time will ilow through line 10, wheel 60, line 12, line 88, wheel 84, line |06 to line I0. At each rotation of the motor, this current is interrupted once. When the device is started, wheels 84 and 86 are set so that current can ilow across them, while the non-.

conducting portions of their peripheries are spaced from the contacts by an angle equal to the angle between the 0 and 6 positions on the dial 82. As soon as current flows through wheel 60, solenoid |08 is energized and pulls rod |I0 toward the right (Fig. 9). As the current is broken by wheel 60, the solenoid is deenergized and the rod |I0 moves to the left, imparting a clockwise motion to wheel II8 and thereby to shaft 88. At the same time, this impulse of current has ilowed through wheel 84 to line I0 and has caused the dropping of one bomb. At each -interruption of current by the wheel 60, the solenoid is operated and released, and thus the dial 82 and the wheel 88 move step-by-step to the 0 position. When this position is reached, the insulating portions of wheels 84 and 86 are opposite the contacts, so that the current is broken. Therefore, no more impulses are sentto theline I0, nor is the solenoid |08 operated to move the shaft 88 any further. 1

It is thus apparent that the mechanism will drop the required number of bombs at `the desired spacing on the ground, and then will cease to operate until it is reset to drop more bombs.

'I'he circuit further includes a rheostat |36 for the control of panel lights |38 with covers |38, a release signal light |40 which is illuminated at each operation of the bomb release mechanism, and a motor signal light |42 which indicates that the switch 30 is closed and that the motor is operating.

In themechanism shown by Figs.l 14 to 16,'

assen order, but also for indicating how many bombs remain available in the bomb rack at any time.

In this device, the wheels 94 and 90 serving to control respectively the bomb dropplllg mechanism and the step-by-step mechanism are uti- .f

lized in the same manner .as described above. These wheels are mounted on a shaft |50 longitudinally shiftable in bearings |52 andhaving at its end a knob |54 provided `with a pointer |56 in front of the dial |58. A coil spring |60 engaging at one end against the bearing |52 and at the other against a plate resting against the hub of wheel 90 surrounds the shaft |50 and urges it constantly outward (to the right in Fig. 15).

Rigidly mounted on the shaft |50 is a disc |02 provided with a. series of holes it arranged in a circle around the axis of the shaft. A sleeve |66 rotatably mounted on the shaft |50 has rigid therewith a lever |68 carrying at its end a pin |10 spaced the same distance from the axis of the shaft as the .holes Idand therefore engageable therein.

A pointer |12 is arranged on the sleeve |56 in front f the dial |58, this pointer preferably being mounted on the sleeve so that it can be turned with respect thereto if suicient force i's applied.

Rigid with the sleeve |66 are two ratchet discs |14 and |16, disc |15 being also pinned to lever |68. These discs are engaged byV a pawl |10, spring pressed intolcontact therewith yso as to limit their rotation in one direction. They are also engaged by a pawl |80 mounted on a leve'r |82, corresponding to lever ||6 of Fig. 9, and operated by a pin ||2, rod ||0, solenoid |08 and spring |26. The pawls, however, as it will be noted, are arranged so that the wheels can be moved during the energization of the solenoid, while the wheels remain unmoved during the return of the solenoid core I0 under the action of spring |28.

The construction described above is operated in the following manner:

Assuming that at the start of the flight there are fty bombs in the rack. The pointer |12 is moved by hand or in any other suitable manner until it is opposite the number 50 on the dial. The pointer |56 is at 0. Now when in flight it is desired to release ten bombs, the knob |50 is pressed in, so that shaft |50 slides against the force of spring |60 and moves disc |62 until holes |64 disengage pin |10. The lever is then turned until pointer |58 is opposite the .number 10 on dial |58. This of course turns wheels 90 and 96, so

that intermittent impulses from the motor may be transmitted to the bomb dropping mechanism and to the solenoid |08. When handle |56 is released, spring |60 moves shaft |50 toward the right (Fig. 13) so that another of holes |64 engages pin |10. Now at each rotation of the motor, as described above in connection with Figs. l to 13, solenoid |08 is operated and thus shifts sleeve |56 and therewith shaft |50 by one step. This movement of sleeve |66 simultaneously moves pointer i12 downward one step, while pointer |56 also moves counter-clockwise. When pointer |56 reaches 0, the solenoid will cease to be energized and therefore the movement will stop. At the same time it will be noticed that pointer 50 will likewise move down ten steps and will indicate that there are only forty bombs left in the rack.

While I have described herein one embodiment of my invention I wish it to be understood that I do not intend to limit myself thereby except within the scope of the appended claims. l

I claim:

l. Afdevice of the class described comprising means settable to a plurality of positions and incapable in one of said positions of transmitting impulses, means operable independently of the position of said iirst means for imparting intermittent impulses to said ilrst means, and impulse responsive means operable when said rst means is in a transmitting position by each impulse to move said rst means to a different posigon in the direction of a non-transmitting posi- -2. A variable tram-release mechanism comprising an electric motor, a circuit to supply .current to said motor, a second electric circuit,

means in said second circuit operated by said motor for periodically interrupting said second circuit, a second interrupting means only in said second circuit havinga non-conducting position, and means controlled by operation of said-first interrupting means to move said second interrupting means towards non-conducting position.

3. A variable train release mechanism comprising an electric motor, a circuit to supply current to said motor, a second electric circuit, means in said secondcircuit operated by said motor for periodically interrupting said second circuit so as ,to send periodic impulses therethrough means onlyin said second circuit movable to a. plurality of positions in at least one of which said second circuit is interrupted, and means controlled by said impulses to move said second means at each impulse to a different position in the direction of said interrupting position.

4. In a device for transmitting intermittent impulses from a source of current to a bomb rack, an electric motor, interrupting means in the circuit between the source and the bomb rack driven by said motor, a tachometer connected to said motor to indicate the rate thereof, said tachometer .including a cooperating dial and index, said dial having circles thereon representing differentw ground speeds andhaving curves intersecting said circles representing different lineal spacings between operations of said interrupting means, and means to vary the speed of the motor.

5. In a bomb release control mechanism for aircraft comprising a motor and-means controlled by said motor to control the release of bombs, means to vary the speed of said motor, and a tachometer operably connectedI to said motor,

as f

said tachometer having a dial graduated to indiy cate horizontal spacing between bombs in accordance with the speed of the aircraft.

6. In a device of the character described, an

electric motor, means to supply current to said motor, an electric circuit, means in said circuit operated by said motor for interrupting the circuit ateach revolution of the motor, a movable member having conducting and non-conducting portions, contacts in said circuit spaced from each other in the direction of movement of and engaging said member, whereby in one position of said member said circuit is interrupted, and means operated by electrical impulses from said rst means for imparting a step-by-step movement to said member upon each revolution of said first motor. l

7. In a device of the character described, an electric motor, means to supply current to said motor, a circuit for Iconducting current from a source to a bomb release mechanism, means in said circuit operated by said motor for interrupting the circuit at each revolution of the motor, a wheel having a portion of its periphery formed of conducting material, a shaft on which `said wheel is mounted, a second similar wheel on said shaft, contacts in said circuit engaging the periphery of said rst wheel, whereby in one position of said ilrst wheel said circuit is interrupted, contacts engaging the periphery of said second wheel, means connecting one of said second contacts to said circuit, a solenoid connected to the other of said secondcontacts, and means operated by said solenoid for imparting a step-by-step,

motor, a circuit for conducting current froml a source to a bomb release mechanism, means in said circuit operated by said motor for interrupting the circuit at eachrevolution of the motor, a wheel having a portion of its periphery formed of conducting material, a shaft on which said wheel is mounted, manual means to move saidishaft, a dial and index relatively movable and one connected to said shaft for rotation therewith, a second similar'wheel' on said shaft, contacts in said circuitl engaging the periphery of said rst fili wheel, whereby in one position of lsaid first wheel said circuit is interrupted, contacts engaging the periphery of said second wheel, means connecting one of said secondcontacts to Said circuit, a solenoid connected to the other of said second contacts, and means operated by said solenoid for imparting a step-by-step movement to said shaft upon each operation oi4 said ilrst interrupting means.

10. In a device as claimed in claim 9, in which said index is connected to the shaft, a second index settable independently of said shaft, and I means for connectingsaid second indexY to said shaftfor movement therewith during rotation of said. shaft by said solenoid.V

1l. A variable train release mechanism Afor use* in aircraft comprising an electric motor, means to supply current to said motor, an electric circuit, means in said circuit operated'by said motor for periodically interrupting, said circuit .so as to send periodic impulses therethrough, means in said circuit movable to a plurality of positions in at least one of which said circuit is interrupted, means controlled by said impulses to move second means at each impulse to a dinerent position inthe direction of said interrupting poai` tion, means to vary the 1' ,t ci said motor, and a vtachoineter operably connected to said motor, said tachonieter having a dial medicated to indicatehorizontal spacing between impulses in accordance with thesneed oi the aircraft.

electric motor, means to supply current to said motor, an l electric circuit, means in said circuit own-ated by said motorini interrupting the circuit at each revoiution of the motor, .a shaft, means on said sha'it for breaking said .circuit in one position thereof, a' solenoid, means to energias said solenoid at each revolution ci said motor, and means operated by said solenoid ior imparting a step-by-stcp movement to said shaft towards circuitbreaking position upon cosh resolution ci said motor, said solenoid operating means mounted on said shaft and having -an inoperative position correspondingv to the said circuit breaklng position.

13. In a device of the character described, an electric motor, means to supply current to said motor, an electric circuit, means in said circuit operated by said motor for interrupting the circuit at each revolution of thev motor, a shaft, means on said shaft for breaking `said circuit in one position thereof, a solenoid, means to energize said solenoid at each revolution of said motor, means operated. by said solenoid for imparting a stepby-step movement to said shaft towards circuit breaking position upon each revolution of said motor, said shaft having an index thereon, a sleeve on said shaft, a second index on said sleeve, manual means to turn said shaft, and means to adjust the angular relation of said sleeve' and shaft.

14. In a device of the character described. an electric motor, means to supply current to said motor, an electric circuit, means in said circuit operated by said motor for interrupting the circuit at each revolution of thevmotor, a shaft,

ymeans on said shaft for breakingsaid circuit in one position thereof, a solenoid, means to energize said solenoid at each revolution of said motor, means operated by said solenoid for imparting a step-by-step movement to said shaft towards circuit breaking position upon each revolution of said motor,'said shaft having an index thereon, a sleeve on said shaft, a s'econd index on said sleeve.

manual means to turn said shaft, and means to 'adjust the angular relation of said sleeve and shaft, said solenoid operating on said sleeve.

' l5. In Aa device of the character described, an electric motor, meansl to supply current to said' motor, an electric circuit, means in said circuit operated by said motor forinterrupting the circuitat each revolution of the motor, a shaft, means on' said shaft `for breaking said circuit in one position thereof, a, solenoid, means to energine said solenoid at each revolution of said motor, means operated by said solenoid for imparting a step-by-step movement to said shaft towards circuit breaking position upon each revolut-ion of said motor, said shaft having an index thereon, a sleeve on said shaft, a second index on said sleeve, manual means to turn said shaft, and cooperating coupling means on said sleeve and shaft to permit angular adjustment therebetween, said solenoid operating on said sleeve.

16. In a device of the character described. an electric motor. means to supply current to said motor, a circuit for conducting current from a source to a bomb release mechanism, means in said circuit operated by said motor for. interl rupting the circuit periodically duringrevolution oi the motor, a wheel having a portion of its periphery formed of conducting material, ka shaft @aging the periphery of said first wheel. whereby i2. In a device of the character described, an

in one position of said nrst wheel said cuit isinterrnpted, contacts engaging the pe phery of said second wheel, means connecting one of said second contacts to said circuit and means connected to the other of said second contacts ior imparting a step-by-step'movement to said shaft upon each operation oi said iirst interrotating m.

i?. In o device of the character described. an electric motor, means to supply current tc said motor, an electric circuit, means' in said circuit operated by said motor for interrupting the cirss 2,209,380 cuit periodically during revolution of the motor,

a shaft, means controlled by said shaft for breaking said circuit in one position thereof, and means operated by said circuit interrupting means for imparting a step-by-step movement to said shaft towards circuit breaking position during revolution of said motor, said last means being mounted on said shaft and having an inoperativeposition corresponding to the said circuit breaking position.

18. Ina device of the character described, an electric motor, means to supply current to said motor, an electric circuit, means in said circuit operated by said motor for interrupting the circuit periodically during revolution of the motor, a shaft, means controlled by said shaft for breaking said circuit in one position thereof, means operated by said circuit interrupting means for imparting a step-by-step movement to said shaft towards circuit breaking position during revolution of said motor, said shaft having an index thereon, a sleeve on said shaft, a second index on said sleeve, manual means to turn said shaft, and means to adjust the angular relation of said sleeve and shaft.

19. In a device of the character described, an electric motor, means to supply current to said motor, an electric circuit, means in said circuit operated by said motor for interrupting the circuit periodically during revolution of the motor, a shaft, means controlled by said shaft for breaking said circuit in one position thereof, means operated by said circuit interrupting means for imparting a step-by-step movement to-said shaft towards circuit breaking position during revolution of said motor, said shaft having an index thereon,a sleeve on said shaft, a second index on said sleeve, manual means to turn said shaft, and means to adjust the angular relation of said sleeve and shaft, said shaft moving means operating on said sleeve.

20. In a device of the character described, an electric motor, means to supply current to said motor, an electric circuit, means in said circuit operated by said motor for interrupting the circuit periodically during revolution of the motor, a shaft, means controlled by said shaft for breaking said circuit in one position thereof, means operated by said circuit interrupting meansfor imparting a step-by-step movement to said shaft towards circuit breaking position duringrevolution of said motor, said shaft having an index thereon, a sleeve on-said shaft, a second index on said sleeve, manual means to turn said shaft, and cooperating coupling means on said sleeve and shaft to permit angular adjustment therebetween, said shaft moving means operating on said sleeve.

21. In a device of the character described, an electric motor, means to supply current to said motor, an electric circuit, means in said circuit operated by said motor for interrupting the circuit periodically during operation of the motor, a movable member having conducting and nonconducting portions, contacts in said circuit spaced from each other in the direction of movement, of and engaging said member, whereby in one position of said member said circuit is interrupted, and means operated by electrical impulses from said first means for imparting a step-by-step movement to said member upon each operation of said rst means.

RALPH L. BELL. 

